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<A HREF="contents.html"><IMG TITLE="Programming in Lua (first edition)" SRC="capa.jpg" ALT="" ALIGN="left"></A>This first edition was written for Lua 5.0. While still largely relevant for later versions, there are some differences.<BR>The third edition targets Lua 5.2 and is available at <A HREF="http://www.amazon.com/exec/obidos/ASIN/859037985X/theprogrammil3-20">Amazon</A> and other bookstores.<BR>By buying the book, you also help to <A HREF="../donations.html">support the Lua project</A>.
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<font color="gray">Programming in </font><font color="blue"> Lua</font>
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<td width="80%" align="center"><a href="contents.html#P1">Part I. The Language</a>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<a href="contents.html#3">Chapter 3. Expressions</a></td>
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<p><h2>3.4 &ndash; Concatenation</h2>
Lua denotes the string concatenation operator
by "<code>..</code>" (two dots).
If any of its operands is a number,
Lua converts that number to a string.
<pre>
    print("Hello " .. "World")  --> Hello World
    print(0 .. 1)               --> 01
</pre>
Remember that strings in Lua are immutable values.
The concatenation operator always creates a new string,
without any modification to its operands:
<pre>
    a = "Hello"
    print(a .. " World")   --> Hello World
    print(a)               --> Hello
</pre>

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  Copyright &copy; 2003&ndash;2004 Roberto Ierusalimschy.  All rights reserved.
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